Exclusively for purposes of securing the financing of port or harbor infrastructure, any harbor agency may borrow funds from, or otherwise secure financing through, an authority at the interest rate or rates, with the maturity date or dates, payment, pledge, security, default, remedy, and other terms and conditions specified in bonds of the harbor agency or obtain a loan, loan purchase, installment purchase, lease, or other agreement between the authority and the harbor agency. The harbor agency also may enter into any agreement for liquidity or credit enhancement that may be necessary or appropriate, as determined by the authority and consistent with other provisions of law, in connection with the borrowing or loan. This section provides a complete, additional, and alternative method for performing the acts authorized by this section.